William



' 1 1,618,655 9 7" w. D. SMITH COMBINED MAGNETO POST AND SWITCH Filed Jan. 23 1925 tion typle Patent ed Feb. 22, 1927. I

' UNITED STATES PATENT OFFICE.

WILLIAM DOUGLAS SMITH, OF LUMBEK BRIDGE, NORTH CAROLE.

COMBINED MAGNETO POST AN D SWITCH.

Application filed January An object of my invention is to provide a combined magneto post and switch which will prevent a traction engine of the mtern-al combustion type from rearing when the.

front portion thereof reaches av dangerous degree of elevation.

Another object of myinvention is to provide in a magneto post a liquid contact switch-which will automatically break the ignition. circuit of the. propelling engine when an end of the engine reaches a dangerous angle of elevation with regard to the other end of the engine.

Another object of invention is to provide means for prevention of over-turning of traction engines of the internal combus- Anot er object of invention is to provide a magneto post for internal. combustion en ines in combination with a liquid contact switch made integral therewith. Having thus stated some of the objects of invention, a brief description of the drawin s follows:

f igurell is a perspective view of my combined magneto post and switch.

Figure 2 .is a perspective view of the cap which screws on the end of the combined ma' eto post and switch.

igure 3 IS a perspective view of the end of the combined magneto post and switch which screws into the internal combustion en ine.

igure 4 is a sectional view through the longitudinal center of my device.

Figure 5 is a sectional view of one form of the cap 13.

Figure 6 is a view of the ring 14 secured to the inner side of the cap 13.

Figure 7 is a view of the member 11 looking towards the base of the device. v

igure 8 is a viewpartially in section of the brush'mounted in the base of my device.

Figure 9 isa side elevation partially in section, showing the device tilted to a point where the contact is broken.-

Having thus briefly described the different figures in the drawings, a more detailed description will be given,'in which like numerals represent corresponding parts thru- 23, 1925. Serial No. 1,273.

' only limitation bein that it shall not be subject to the action of the mercury contained in the cup. This member 3 becomes smaller as it approaches the base portion 2 at the point 4 and is secured to the base portion 2 at the point 5 by means of threads or by being moulded in position. .This member 3 continues to extend into the base 1 thru the hole 6 in the base in the form of the elongated portion or stem 8. In the base of the cup 3 just below the retracted portion 4 there is secured the annular member 11, the part 9 of which extends thru the hole 6 in the lower portion of the cup-shaped member 3. At the lower end of this ste'm'9 there is secured the conventional brush 10.

The larger end of the cup-shaped member 3 has threads 7 thereon, and a cap 13 is secured to the member 3 by means of the threads 12. Within the cavity C the member 14 is secured to the cap 13 b means of the bolt 15 which penetrates t e cap 13. Said bolt and member 14 are held in position by means of the nut 17. Another nut 16 is mounted on the bolt 15 for purposes of connecting a wire thereto.

In case the cap is not made of a non conducting material, a non-condu'ctin gasket 18 is placed between the cup-s aped member 3 and the cap 13. This also extends between the member 14 and the cap 13 for purposes of insulation. In this last-dd scribed embodiment the insulating washer 19 is secured on the outside of the cap 13 between said cap and the nut 17 It might be stated that the base 1 is preferably made of steel or iron, tho it is to be understood that it may be made inte ral with the member 3. It is of course evi cut that the member 11, and the parts 9 and 10 thereof are to be made of any material capable of conducting an electric current, while at the same time this material must be of such quality that it will not be acted-upon by the mercury contained in the cavity C. A high grade of steel is desirable for the making of the part 11.

V in Figure 9, and the ignition circuit will be When the device is assembled mercury is poured into the cavity C by removing the cap 13. The quantity of mercury or other conductive liquid to be poured'into the cavity C is to be governed by the angle at which it is desired that the contact should be broken. Figure 9 shows enough mercury in the cavity C to cause the circuit to be broken when the switch has reached an angle of elevation of forty-five degrees. It is of course, to be understood that when a smaller amount of mercury is poured into the cavity C that the circuit will be broken before the large end of the switch reaches an elevation of forty-five degrees from the horizontal.

The method of operation is as follows:

This device is capable of being attached to any tractor of the internal combustion type, and especially to the F ordson tractor. The ordinary magneto post is removed and discarded, and instead thereof my device is mounted on the tractor in its stead. The wiring of the tractor leading from the magneto post is attached to the part 15 of my device, instead of being attached to the top of the old magneto post. The engine of the tractor is started and functions perfectly as long as the tractor is on comparatively level ground. When the tractor proceeds. over ground which is not level there is danger of the ordinary tractor raising itself up in front and falling over backwards on the driver. With my device attached to the engine it will be impossible for the tractor to fall backwards, for the reason that when the front end of the tractor has reached a dan erous elevation the mercury in the cavity will have reached the position shown broken and the danger of overturning averted.

It might also be stated that the concave shape of the member 11 will compensate for the slight expansion of the mercury when the engine becomes heated or when the engine is exposed to the rays of the sun.

I have described a preferred embodiment of my inveiition, but I desire it to be understood that slight changes may be made in its structure as may fall within the scope of the appended claims.

What I claim .and desire to secure by Letters Patent is:

1. In a magneto post for internal combustion engines, a liquid contact switch 01m.- ing a part of said magneto post.

2. In a magneto post for internal combustion engines, a base portion adapted to be attached to the engine, a hollow member secured to said base portion, a metallic member mounted in the hollow member and extending thru the base portion, a cap on one end of the hollow portion, a metallic member secured to the inner side of said cap, metallic means extending thru the cap, and mercury contained in the hollow member.

3. In a combined magneto 0st and switch for internal combustion engmes, means for automatically breaking an electric current assed thru said magneto post and switch y a tilting of the combined magneto post and switch to a predetermined degree from the horizontal.

In witness that I claim the foregoing as my own, I have hereunto aifixed my signature this the 8th day of January, 1925.

WILLIAM DOUGLAS SMITH. 

